全文获取类型
收费全文 | 75361篇 |
免费 | 5399篇 |
国内免费 | 163篇 |
专业分类
耳鼻咽喉 | 599篇 |
儿科学 | 2812篇 |
妇产科学 | 2476篇 |
基础医学 | 9172篇 |
口腔科学 | 1029篇 |
临床医学 | 13194篇 |
内科学 | 13440篇 |
皮肤病学 | 1115篇 |
神经病学 | 6915篇 |
特种医学 | 1355篇 |
外国民族医学 | 33篇 |
外科学 | 6452篇 |
综合类 | 968篇 |
一般理论 | 129篇 |
预防医学 | 10567篇 |
眼科学 | 863篇 |
药学 | 4223篇 |
1篇 | |
中国医学 | 103篇 |
肿瘤学 | 5477篇 |
出版年
2023年 | 446篇 |
2022年 | 635篇 |
2021年 | 1432篇 |
2020年 | 1044篇 |
2019年 | 1717篇 |
2018年 | 1917篇 |
2017年 | 1343篇 |
2016年 | 1569篇 |
2015年 | 1696篇 |
2014年 | 2262篇 |
2013年 | 3671篇 |
2012年 | 5189篇 |
2011年 | 5465篇 |
2010年 | 2944篇 |
2009年 | 2723篇 |
2008年 | 4902篇 |
2007年 | 5459篇 |
2006年 | 5298篇 |
2005年 | 5107篇 |
2004年 | 4922篇 |
2003年 | 4673篇 |
2002年 | 4407篇 |
2001年 | 615篇 |
2000年 | 454篇 |
1999年 | 610篇 |
1998年 | 996篇 |
1997年 | 758篇 |
1996年 | 684篇 |
1995年 | 593篇 |
1994年 | 567篇 |
1993年 | 564篇 |
1992年 | 386篇 |
1991年 | 329篇 |
1990年 | 315篇 |
1989年 | 280篇 |
1988年 | 273篇 |
1987年 | 263篇 |
1986年 | 248篇 |
1985年 | 292篇 |
1984年 | 298篇 |
1983年 | 305篇 |
1982年 | 382篇 |
1981年 | 361篇 |
1980年 | 304篇 |
1979年 | 175篇 |
1978年 | 163篇 |
1977年 | 175篇 |
1976年 | 160篇 |
1975年 | 136篇 |
1974年 | 123篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
21.
22.
23.
24.
PROBLEM: Recent developments in providing care to children with emotional and behavioral disorders, especially those with serious emotional disturbance, have included the establishment of systems of care. Guided by a set of principles and values, these systems of care have organized and delivered services to children and families with complex needs. To date, nurses have not had a salient role in systems of care. RESULTS: It is estimated that 20% of American children and adolescents have an emotional or mental disorder. As many as two thirds of these children are not receiving services. Systems of care have been funded to provide services for these children, particularly for the most severely affected. To date, nursing has not had a prominent role in these systems of care. CONCLUSIONS: Based on their knowledge, skills, and holistic approach to care, nurses could better integrate nursing care into systems of care. Possible roles as case managers, primary therapists, in-home interventionists, and in educational programs are suggested. 相似文献
25.
Sandra Urdaneta Hartmann Brian Wigdahl Elizabeth B Neely Cheston M Berlin Cara-Lynne Schengrund Hung-Mo Lin Mary K Howett 《Journal of human lactation》2006,22(1):61-74
Reduction of transmission of human immunodeficiency virus type 1 (HIV-1) through human milk is needed. Alkyl sulfates such as sodium dodecyl sulfate (SDS) are microbicidal against HIV-1 at low concentrations, have little to no toxicity, and are inexpensive. The authors have reported that treatment of HIV-1-infected human milk with < or = 1% (10 mg/mL) SDS for 10 minutes inactivates cell-free and cell-associated virus. The SDS can be removed with a commercially available resin after treatment without recovery of viral infectivity. In this article, the authors report results of selective biochemical analyses (ie, protein, immunoglobulins, lipids, cells, and electrolytes) of human milk subjected to SDS treatment and removal. The SDS treatment or removal had no significant effects on the milk components studied. Therefore, the use of alkyl sulfate microbicides to treat milk from HIV-1-positive women may be a simple, practical, and nutritionally sound way to prevent or reduce transmission of HIV-1 while still feeding with mother's own milk. 相似文献
26.
27.
29.
Edward J Boland Mary MacDougall David L Carnes Sabine H Dickens 《Dental materials》2006,22(4):338-345
Recently, a resin-based calcium phosphate cement (RCPC) has been reported as a remineralizing pulp-capping or lining cement. RCPC consists mainly of tetracalcium and dicalcium phosphates, ethoxylated bisphenol A dimethacrylate and pyromellitic glycerol dimethacrylate monomers and photo- and chemical initiators. OBJECTIVES: Here, the cytotoxic effects of RCPC were evaluated. The hypothesis was that RCPC induced only minor cytotoxic response in immortalized murine odontoblast and pulp cells, comparable to that produced by similar dimethacrylates due to unpolymerized dimethacrylate monomer present after curing. METHODS: Cytotoxicity was determined following the changes in cell succinate dehydrogenase activity after 24 h exposure to the cement components and after a 24 h recovery period. A fourfold range of concentrations was tested of the monomers, the eluate of cured RCPC leached in Dulbecco's modified Eagle's medium, and crushed cured cement in dimethyl sulfoxide. RESULTS: The monomers themselves had cytotoxicities similar to those reported for other dimethacrylates, although they are significantly less toxic than Bis-GMA. Differential cell sensitivity was demonstrated, with the pulp cells having greater sensitivity to the unpolymerized monomer than the odontoblast-like cells. The leached components have cytotoxicity similar to that of the free monomers. The crushed material demonstrated no apparent cytotoxicity at the dilutions tested. SIGNIFICANCE: These data demonstrate that RCPC has an in vitro cytotoxicity that is comparable to other materials containing dimethacrylate monomers and suggest that the material may be suitable for use in dental restorations. The data also indicate that the pulp cells appear more sensitive to dimethacrylates than the odontoblasts. 相似文献
30.